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1.
<正>依据地方绿色文化和红色文化开展的少先队员活动,增强了少先队员环保意识和红色文化素养,提高了团队协作能力和社会实践能力,促进了家校合作和家庭教育效果的提升,提升了少先队员活动的实效性和影响力。少先队员是祖国未来的建设者和接班人,他们的成长和发展关系到国家的未来。在少先队员的成长过程中,地方绿色文化和红色文化具有重要的教育价值,对他们的价值观形成和社会责任感培养具有积极的影响。  相似文献   

2.
观点     
《绿叶》2014,(10):114-115
正乡愁(Nostalgia)是浪漫主义的一个重要内容,是现代性的产物,是现代化生产出来的一种情绪。人们对乡村有着爱恨情仇的矛盾和复杂的感情:乡村既是逃离的对象,又是眷恋的对象。乡村曾经遭受了诅咒,然而,当人们进入城市之后,乡村被对象化,成为了相对遥远的"风景",转变为审美和抒情的对象。乡村和城市的分裂和对立造成了现代的病态和创痛。人们在乡村和城市之间游弋徘徊,充满了矛盾和困惑。任何片面地赋予城市或乡村优先价值都是偏颇的。只有当乡村和城市获得和解,重新建立亲密的关系,工业生产和农业生产、体力劳动和脑力劳动的分裂被克服,人类才能重建健全的人性和社会。  相似文献   

3.
为实现深度脱水污泥的改性和资源化利用,以上海某城市污水处理厂的两种不同含水率的深度脱水污泥A和B为例,通过向污泥中掺混土壤,研究土壤对污泥含水率、有机质、抗压强度、恶臭和植物毒性等的影响,探索其用作填埋场封场覆盖绿化用土的可行性.结果表明,掺混土壤可明显降低污泥含水率、有机质和臭气强度,并显著提高其抗压强度和种子发芽率,且相关性分析表明,土壤对污泥的有机质、臭气强度和浸出液种子发芽率的改善效果较强;当土壤添加量分别为60%和30%时,污泥A和B的抗压强度可分别由32.99kPa和196.67kPa的初始值增加至117.6kPa和227.5kPa,臭气强度可由4.5级和4级下降至2级和1.5级,浸出液白菜种子发芽率可由50%和56.7%增加至90%和80%.改性后的污泥A和B均能满足填埋场封场覆盖绿化用土的要求,实现其资源化利用.  相似文献   

4.
来自国家统计局的消息说,我国重新划分三次产业,今年的统计年报将开始采用新的划分方法进行有关统计。三次产业划分的具体范围是:第一产业包括农、林、牧、渔业;第二产业包括采矿业,制造业,电力、燃气及水的生产和供应业,建筑业;第三产业包括除第一、二产业以外的其他行业,具体包括:交通运输、仓储和邮政业,信息传输、计算机服务和软件业,批发和零售业,住宿和餐饮业,金融业,房地产业,租赁和商务服务业,科学研究、技术服务和地质勘查业,水利、环境和公共设施管理业,居民服务和其他服务业,教育、卫生、社会保障和社会福利业,文化、体育和娱乐…  相似文献   

5.
生态环境是人类生存和社会经济发展的基础,生态环境问题发展具有隐蔽性、渐进性和积累性,其后果则是间接性、全局性和突发性,目前,我国生态环境现状令人担忧,因此,保护和改善生态环境应引起决策者和社会公众的警觉和重视。  相似文献   

6.
环境保护事业在不断地发展,形势喜人,给环保工作提出了新的要求,环保宣教工作也面临新的机遇和挑战。福州市在多年的环境保护宣传教育工作实践和探索中,积累了一定的经验和做法,但同时,我们更希望能借鉴更多先进的经验和做法,不断总结和提高,更多地发现和把握环保宣教工作的特点和规律,更好地服务于环保事业的发展大局。以下为我市环保宣教工作的一些经验和做法:  相似文献   

7.
底泥的氮、磷释放及其微生物影响的研究   总被引:2,自引:0,他引:2  
张恒军  吴群河 《环境技术》2003,41(Z1):20-23
氮和磷在自然界的循环已经引起了人们的关注,一方面因为氮和磷是生态系统中必不可少的营养元素,另一方面过剩的氮和磷会导致水域的富营养化 ,从而使生态平衡遭受破坏.本文综述了水体沉积物中氮和磷受微生物作用进行释放的影响,以及国内外的研究历史和现状.总结了氮磷微生物代谢的特点,并阐述了与传统认识相区别的最新发现和思想.本文试图从理论上说明微生物的氮磷释放机理,通过生物化学和分子动力的角度解释了细菌对氮磷的吸收和释放,即质子动势理论和Pho调控理论.目前,这一领域研究的热点是为了特殊的使用用途对于高效微生物的分离鉴别和组合培养,和对氮磷代谢的影响因素.  相似文献   

8.
在采油清洁生产审核中发现,对生产过程的物质消耗和废物排放难以准确地进行分析和测试。针对这一问题,提出了水平衡分析法。对水平衡及其生产过程进行了评估,分析了清水损耗和废水产生的原因和环节,探讨了节约水资源、提高污水回用率的途径和方法,并提出了改进的目标和对策,形成了清洁生产审核方案。清水、污水平衡分析方法简单可靠,易于实施,同时可以为能量平衡、污染因子平衡的建立和分析提供借鉴和参考。  相似文献   

9.
党的十六大和中央最近召开的人口资源环境工作座谈会,为我们进一步做好环境保护工作指明了奋斗目标和方向。如何把中央的精神与本地的实际相结合,认清形势,周密部署,切实做好环保工作,适应和满足全面建设小康社会的要求,是我们需要认真思考和解决的问题。一、环境保护面临的挑战和机遇襄樊市是国家级历史文化名城和新兴的工业大城市,经过多年来的不懈努力,环境保护工作取得了显著的成效,为今后  相似文献   

10.
乌鲁木齐市是新疆维吾尔自治区的首府。随着开发新疆和建设新疆伟大的社会主义事业的发展,她的中心城市的地位和作用必将得到更大的发挥和加强。但是,由于生产发展,经济繁荣,交通发达,和随之而来的人口增加,就难免产生新的环境问题,比如水质和大气的污染、噪声和固体废物的增加等等。如果对这一点我们现在不去注意或者稍有疏忽,一旦形成公害,那么一定会造成不可弥补的损失。  相似文献   

11.
What size sample is sufficient for spatially sampling ambient groundwater quality? Water quality data are only as spatially accurate as the geographic sampling strategies used to collect them. This research used sequential sampling and regression analysis to evaluate groundwater quality spatial sampling policy changes proposed by California's Department of Water Resources. Iterative or sequential sampling of a hypothetical groundwater basin's water quality produced data sets from sample sizes ranging from 2.8% to 95% coverage of available point sample sites. Contour maps based on these sample data sets were compared to an original (control), mapped hypothetical data set, to determine at which point map information content and pattern portrayal are not improved by increasing sample sizes. Comparing series of contour maps of ground water quality concentration is a common means of evaluating the geographic extent of groundwater quality change. Comparisons included visual inspection of contout maps and statistical tests on digital versions of these map files, including correlation and regression products. This research demonstrated that, down to about 15% sample site coverage, there is no difference between contour maps produced from the different sampling strategies and the contout map of the original data set.  相似文献   

12.
Environmental maps show the probable environmental states of different types of land use or development of landscape in a geographic context. Remotely sensed data are particularly efficient for environmental mapping in order to outline major environmental types. Multiple schemes of image classification used in environmental mapping are either traditionally statistical or heuristic. While the former methods do not take account of spatial variability in space and aerial data, the latter ones does not lend themselves to optimal solutions we present. Novel probabilistic models of piecewise-homogeneous images are used in environmental mapping to segment real images. The models consider both an image and a land cover map. Such a pair constitutes an example of a Markov random field specified by a joint Gibbs probability distribution of images and maps. Parameters of the model are estimated by using a stochastic approximation technique. Its convergence to the desired values is studied experimentally. Addition of spatial attributes appears to be necessary in most areas where the differences in spatial data between regions in the image occur. Experiments in generating the pairs of images and environmental maps and in segmenting the simulated as well as real images are discussed.  相似文献   

13.
Flood inundation maps play a key role in assessment and mitigation of potential flood hazards. However, owing to high costs associated with the conventional flood mapping methods, many communities in the United States lack flood inundation maps. The objective of this study is to develop and examine an economical alternative approach to floodplain mapping using widely available soil survey geographic (SSURGO) database. In this study, floodplain maps are developed for the entire state of Indiana, and some counties in Minnesota, Wisconsin, and Washington states by identifying flood‐prone soil map units based on their attributes. For validation, the flood extents obtained from SSURGO database are compared with the extents from other floodplain maps such as the Federal Emergency Management Agency issued flood insurance rate maps (FIRMs), flood extents observed during past floods, and flood maps derived using digital elevation models. In general, SSURGO‐based floodplain maps (SFMs) are largely in agreement with other flood inundation maps. Specifically, the floodplain extents from SFMs cover 78‐95% area compared to FIRMs and observed flood extents. Thus, albeit with a slight loss in accuracy, the SSURGO approach offers an economical and fast alternative for floodplain mapping. In particular, it has potentially high utility in areas where no detailed flood studies have been conducted.  相似文献   

14.
ABSTRACT: Topographic maps are commonly used to define populations of lakes in regional surveys of surface water quality. To illustrate the effect of different maps on that process, we compared the lakes represented on the 1:250,000-scale maps used for the Northeast Region of the Eastern Lake Survey—Phase I (ELS-I) to the lakes on a sample of large-scale maps (1:24,000 or 1:62,500). Lake areas at or near the lower limit of representation delimited “smallest-lake” values for the compared 1:250,000-scale maps. The regional median for these values was 4.5 hectares (ha) and ranged from 0.6 to 24.8 ha. Lake representation is influenced by cartographic limitations such as map scale, age, and complexity as well as the inherent variability of waterbodies (e.g., water level fluctuations or the creation of reservoirs, beaver impoundments, and oxbows). The total number of lakes on large-scale maps increased markedly as lake area decreased. Approximately 15,700 of the estimated 29,000 lakes in the EPA's Northeast Region were 1 to 4 ha in area. Because maps affect the size distribution of lakes included in a regional survey and because lake areas are thought to modify lake chemistry, maps ultimately affect the estimates of regional surface water quality.  相似文献   

15.
1.Information on all maps, including those which depict characters of the natural environment, is subject to locational error. 2.Locational errors on field-sketched maps are attributable to inaccuracies both in the base map itself and in the method of locating and recording features onto the base map. 3.Two main sources of error associated with field sketch mapping were quantified using the River Corridor Survey maps as an example. First, channel widths are routinely exaggerated on these maps to allow recording of in-channel features. Distortions of river bank length of the order of 25% were shown to arise from a four-fold exaggeration of the width of a sinuous channel. Second, discrepancies in feature location of the order of 20% were found along a 500 m river stretch, although errors could be reduced to approximately 2% if undistorted, large-scale base maps were used. 4.An abundance scale appropriate to the inherent locational inaccuracy was devised to extract semi-quantitative information from River Corridor Surveys recorded on distorted base maps. Application of this scale to 29 River Corridor Survey maps of a 14·5 km river corridor produced a useful representation of environmental gradients within the corridor. 5.With the increasing potential to integrate and analyse environmental information within large computer databases including Geographic Information Systems, it is essential that the level of accuracy is recognised and quantified so that the errors can be allowed for in the development of methods of extracting information from the maps.  相似文献   

16.
/ The preparation of landslide maps is an important step in any landslide hazard assessment. Landslides maps are prepared around the world, but little effort is made to assess their reliability, outline their main characteristics, and pinpoint their limitations. In order to redress this imbalance, the results of a long-term research project in the Upper Tiber River basin in central Italy are used to compare reconnaissance and detailed landslide inventory maps, statistical and geomorphologically based density maps, and landslide hazard maps obtained by multivariate statistical modeling. An attempt is made to discuss advantages and limitations of the available maps, outlining possible applications for decision-makers, land developers, and environmental and civil defence agencies. The Tiber experiment has confirmed that landslides can be cost-effectively mapped by interpreting aerial photographs coupled with field surveys and that errors and uncertainties associated with the inventory can be quantified. The experiment has shown that GIS makes it easy to prepare landslide density maps and facilitates the production of statistically based landslide hazard models. The former supply an overview of the distribution of landslides that is easily comprehended but do not provide insight on the causes of instability. The latter, giving insight into the causes of instability, are diagnostically powerful, but are difficult to prepare and exploit.  相似文献   

17.
/ This paper presents an approach for producing aquifer sensitivity maps from three-dimensional geologic maps, called stack-unit maps. Stack-unit maps depict the succession of geologic materials to a given depth, and aquifer sensitivity maps interpret the successions according totheir ability to transmit potential contaminants. Using McHenry County, Illinois, as a case study, stack-unit maps and an aquifer sensitivity assessment were made to help land-use planners, public health officials, consultants, developers, and the public make informed decisions regarding land use. A map of aquifer sensitivity is important for planning because the county is one of the fastest growing counties in the nation, and highly vulnerable sand and gravel aquifers occur within 6 m of ground surface over 75% of its area. The aquifer sensitivity map can provide guidance to regulators seeking optimal protection of groundwater resources where these resources are particularly vulnerable. In addition, the map can be used to help officials direct waste-disposal and industrial facilities and other sensitive land-use practices to areas where the least damage is likely to occur, thereby reducing potential future liabilities. KEY WORDS: Geologic mapping; Groundwater; Aquifers; Aquifer sensitivity; Land-use planning  相似文献   

18.
ABSTRACT: We evaluated maps of runoff created by means of two automated procedures. We implemented each procedure using precipitation estimates of both 5-km and 10-km resolution from PRISM (Parameter-elevation Regressions on Independent Slopes Model). Our goal was to determine if using the 5-km PRISM estimates would improve map accuracy. Visual inspection showed good general agreement among our runoff maps, as well as between our maps and one produced using a manual method. A quantitative uncertainty analysis comparing runoff interpolated from our maps with gage data that had been withheld showed slightly smaller actual and percentage interpolation errors for the 5-km PRISM-based maps. Our analyses suggest a modest region-wide improvement in runoff map accuracy with the use of PRISM-based precipitation estimates of 5-km (compared to 10-km) resolution.  相似文献   

19.
In spatial planning and environmental management, maps are found very helpful in many situations, but in other situations they may also deepen conflicts or be ignored. This paper addresses the question what explains such phenomena, with particular emphasis on, and reference to, collaborative policymaking settings in the Netherlands. We have elaborated the concept of 'frames' and 'framing' to structure and analyze the function of maps in the context of deliberative policymaking. With help of discourse analysis, a method adopted from the policy sciences, we have observed ongoing multi-actor processes and focused on discussions around maps in several case studies. From the observations of both the maps themselves and the discussions and actions with the maps, we have interpreted the meaning and frames represented 'in' the map images, as well as the various perspectives of actors 'on' the collaborative use of the map. We have conceptualized three fundamentally different perspectives or frames on the function of maps in the decision-making process. The cross-frame debate over maps is illustrated with the recollection of one particular map-making example. We conclude that the conflicts observed in a number of case studies can be adequately explained with help of the three identified frames, and provide some recommendations for the profession of mapping.  相似文献   

20.
As part of the planning process, maps of natural factors are often superimposed in order to identify areas which are suitable or unsuitable for a particular type of resource management. Overlay maps may also be used to identify analysis areas for predictive modeling of resource productivity and ecological response to management. Current interest in applying computer-assisted mapping technology to making overlay maps is drawing attention to geographic information systems for this purpose. The resultant maps, however, may be so inaccurate or unable to capture significant units of productivity and ecological response that they could lead to imperfect or false conclusions. Recommendations are made on how to proceed in light of these problems.  相似文献   

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